相关论文: Perfect cloning of harmonic oscillator coherent st…

This paper has been withdrawn due to a critical error near equation (71). This error causes the entire argument of the paper to collapse. Emmanuel Candes of Stanford discovered the error, and has suggested a correct analysis, which will be…

This paper has been withdrawn by the author(s), due to the requirement of the journal it currently submitted to

We report on experimental implementation of the optimal universal asymmetric 1->2 quantum cloning machine for qubits encoded into polarization states of single photons. Our linear optical machine performs asymmetric cloning by partially…

This submission has been withdrawn by the authors because it is a duplicate of arXiv:hep-ph/0611336. It was due to a technical submission error by the authors.

Perfect cloning of a known set of states with arbitrary prior probabilities is possible if we allow the cloner to sometimes fail completely. In the optimal case the probability of failure is at its minimum allowed by the laws of quantum…

The paper of Unal [J. Math. Phys. 59, 062104 (2018)], though worthy of attention, contains a conclusion that is in error and may mislead the efforts to extend his results. The aim of the present note is twofold: we provide a correction to…

We consider the optimal approximation of certain quantum states of a harmonic oscillator with the superposition of a finite number of coherent states in phase space placed either on an ellipse or on a certain lattice. These scenarios are…

This paper was withdrawn (temporarily?) by the author since an error needs to be corrected.

The representation of the superalgebra so(2,1) that resulted in the relativistic wave equation (2.1) and Eq. (2.4) is fully reducible. In fact, its even part that lead to Eq. (3.1) is the direct sum of two spin 1/2 representations of the…

This paper has been withdrawn by the author due to a crucial error.

We discuss the exact cloning of orthogonal but entangled qubits under local operations and classical communication. The amount of entanglement necessary in blank copy is obtained for various cases. Surprisingly this amount is more than 1…

We derive a tight upper bound for the fidelity of a universal N to M qubit cloner, valid for any M \geq N, where the output of the cloner is required to be supported on the symmetric subspace. Our proof is based on the concatenation of two…

This paper has been withdrawn by the author due to errors.

This paper has been withdrawn by the author due to an error.

We show how to implement the optimal Gaussian $N$-to-$M$ cloning with linear optics and homodyne detection. We also show that the Gaussian $N$-to-$M$ cloning of known-phase coherent states can be performed with the fidelity $\sqrt \frac{2 M…

We compute entanglement cost and distillable entanglement of states supported on symmetric subspace. Not only giving general formula, we apply them to the output states of optimal cloning machines. Surprisingly, under some settings, the…

Again, this preprint has been combined with hep-ph/0207106, which is co-authored by both of us. Therefore, this preprint has been withdrawn. Readers are welcome to refer to hep-ph/0207106.

This paper has been withdrawn by the author due to the unsure solution to the Dyson-Schwinger equation.

This paper has been withdrawn by the author due to a crucial sign error in equation 1.

This paper has been withdrawn since it was an inadvertant double submission. An updated version of the original submission can be found at quant-ph/0505131